How to understand the creation of a child instance of the parent's type?

Question

Java

Found in one example such code.

Parent obj = new Child();
    obj.method();

How is it to be perceived? Where will the methods and properties come from?
Please provide a link where you can read more about it.

Answer 1

https://docs.oracle.com/javase/tutorial/java/IandI...
https://www.tutorialspoint.com/java/java_inheritan...
www.java2s.com/Tutorial/Java/0100__Class-Definitio. ..

Answer 2

Methods and properties will either be inherited from the parent or stored in the child class.
In this case, method() can be in both Child and Parent